Dual control for airplanes



I. M. LADDON AND D. H. REEVES. DUAL CONTROL FOR AIRPLANES.

APPLICATION FILED FEB. 6. 1919.

1,329,415. Patented Feb. 3,1920.

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UNITED STATES PATENT ornion.

ISAAC M. LADDON, F DETROIT, MICHIGAN, AND DONALD H. REEVES, OF DAYTON, OHIO.

DUAL CONTROL FOR. AIRPLANES.

Specification of Letters Patent.

Patented Feb. 3, 1920.

Application filed February 6. 1919. Serial. No. 275.384.

To all whom z'zim-ay concern:

Be it known that we, ISAAC M. LADDON v and DONALD H. REEVES, citizens of the United'States, residing at Detroit, Wayne county, Michigan, and Dayton, Montgomery county, Ohio, respectively, have invented certain new and useful Improvements 111 Dual Controls for Airplanes, of which the following is a specification.

This invention relates to a dual control for airplanes of the type where two control sticks are mounted to move simultaneously fore and aft to control the horizontal rudder and to move simultaneously laterally to control the ailerons.

The object of the invention is to produce a dual control of a few number of parts, that is simple to make and to assemble, which is light in weight and adapted for quantity production.

Other objects and advantages will appear as the description proceeds.

In the drawings illustrating an embodiment of our invention, Figure 1 is a side View of the dual control, parts being shown in section; Fig. 2 is a view along the broken line 22 of Fig. 1 some parts being shown in section; Fig. 3 is a plan view, on a smaller scale of the device and the associated foot control; andFig. 4, is a section on the line 44 of Fig. 1.

Referring now to the drawings in which similar reference characters indicate similar parts, 1 indicates a tube mounted transversely of the fuselage to rotate in bearings 2 and 3. As is usual this tube carries upwardly extending arms 4 and 5, to the ends of which are attached elevator control wires 6'and 7. It will be understood that another pair of downwardly extending arms are carried by the tube 1, to which arms are attached another pair of elevator control wires. These latter elements are all well known and are not illustrated.

. usual.

latched in position 'by a pin 12, carried by a spring clip 13, which spring clip is'held by screws 14 to the socket tube 9. The pin 12 extends through registering holes in the socket tube 9, and the stick 11. Element 11 while usually known as a stick is preferably made out of steel tubing. Manipulation of the finger piece 15, carried by the clip 13 disengages the pin 12, from the stick and enables it to be taken out.

A loosely swiveled sleeve 16, is mounted on and carried by the socket tube 9. The sleeve 16 is rotatable on the axis 17-17, which is the common axis for the stick 11, and socket tube 9. The sleeve 16, is provided with a rather broad, heavy forwardly extending lug 18, preferably made integral therewith. This lug 18 is machined to have two parallel, vertically extending bearing surfaces 19 and 20.

Embracing this lug 18, is a stirrup 21, provided with vertically disposed flanges 22 and 23 bearing against the vertically disposed surfaces 19 and 20 of the lug 18. The stirrup 21 is pivoted to the lug 18, by means of a bolt 24, extending through suitably drilled holes in the flanges 22 and 23 and the lug 18.

The forward steering stick 25, is provided stirrup embraces and is pivoted to a longitudinally extending tube 27, the bolt 25 serving as a pivot and permitting fore and aft movement of the stick 25.

The tube 27 extends longitudinally of the fuselage and is pivoted in bearings 28 and 29, to rotate on itsown axis. The bearing 29, is a thrust bearing. Movement of the stick 25 laterally will evidently rotate the tube 27 on its own axis. The bearing 28 is supported on a suitable standard 30. The thrust bearing 29, may be supported on a suitable standard 31.

The tube 27 is provided with the usual arcuate segments 32 and 33, rigid therewith and extending laterally therefrom; The

usual aileron control wires 34: and 35, are 7 attached to the respective'segments to operate the ailerons in opposite directions as is Lateral movement of the stick 25, it is evident, will operate the ailerons.

Pivoted to the stick 25 a short distance above its lower end, on a transversely extending ivot bolt 36, is a stirrup 37. The stirrup 37, and the already described stirrup 21 are each rigid with the horizontally extending connecting tube 38.

The axis of the tube 38 is indicated'by the line AA, the axis of the tube 27 by the line AA, the axis of the stick 25, by the line B-B, and the line through the centers of the pivot bolts 10 and 24, by the line BB. It will be noted that the lines A-A and B-B are respectively parallel to the lines AA, and BB, thus forming a parallelogram. WVhile this condition is advisable in order to secure uniform motion of the two sticks, it is not necessary to the operation.

The tube 38, and its mounting with respect to the two steering sticks is the important feature of this invention. The tube 38, transmits, from one stick to the other, fore and aft movement, it acting, during such transmission, as a tension or compression element. The tube 38, further transmits lateral movement from either stick to the other, it acting during such transmission, as a torsion element. When the stick 11, is moved laterally the movement is transmitted to the sleeve 16, and lug 18, thence to the stirrup 21, through the tube 38', and stirrup 37, to the stick 25, to move it laterally, to rotate the tube 27, and so actuate the ailerons.

Lateral movement of the stick 25, will of course cause a transmission of forces in the opposite direction to move the stick 11 laterally. During the transmission of lateral movement from either stick to the other any given point on the axis of the tube 88, the line AA, describes an arc, the center of which is in the line AA. During this transmission of lateral movement from either stick to the other the sleeve 16 rotates slightly and so prevents binding of the parts.

The sleeve 16, is held in position on the socket tube 9, by a collar 89. The sticks 25 and 11, may be provided with the usual hand grips 40. In order to give the rear pilot more room the stick 11, is shown at a somewhatditferent angle than the angle of'thestick 25.

V The usual foot bar 41, for the vertical rudder is mounted on a standard 42. The already described double function of the tube 38, eliminatesthe necessity of the tube 27 extending all the way from one stick to the other. In the space thereby gained the 7 foot bar 41 is mounted;

Another foot bar 43, for the other pilot is mounted on the standard 31, the two foot bars being connected together, as is usual, by the cords 44, for simultaneous operation. The foot bar 41, may carry the usual controls 45, for the vertical rudder. The usual foot pedals are indicated at 46.

While there has been illustrated oneembodiment of our invention, it should be ment about axes located substantially at the ends of said elements, and a single rigid element, connecting-said two control elements, to transmit fore and aft, and lateral, movement, from one control element to the other, said rigid element being the sole connecting means between said control elements.

2. In a dual control, two control elements, pivoted at their ends for fore and aft, and lateral, movement and a single rigid element, connected to said control elements above the lower end of each, to transmit fore and aft and lateral, movement, from either control element to the other, the said rigid element, during said lateral movement moving about the same aXis about which the lateral movement of one of the control elements takes place, said rigid element being the sole connecting means between said control elements.

3. In a dual control, two control elements pivoted at their ends for fore and aft, and lateral, movement, and a single rigid element connected at its opposite ends to the said control elements at points located a short distance from the pivoted ends of said control elements, to transmit compression and tension, for fore and aft move ment, and to transmit torsion, for lateral movement, from one control element to the other, said rigid element being the sole connecting means between said control elements. 7

4. In a dual control, two control elements pivoted at their ends for fore and aft, and lateral, movement, and a single rigid element connected at its opposite ends to the said control elements at points located a short distance from the pivoted 'ends of sion and tension, for fore and aft movement, and to transmit torsion, for lateral' movement, from one control element to the other, sald rigid means, during said lateral movement, mov1ng in an arc the center of which is substantially coincident with the axis about which the lateral movement of one of said control elements takes place, said rigid element being the sole connecting means between saidcontrol elements.

5. In a dual control, two control elements pivoted tor foreand aft, and lateral, movement, asingle rigid connecting means to transmit fore and aft, and lateral movement, from one control'element to the other,

'said'rigid connecting means moving in an are during the transmission of lateral move ment, said rigid connecting means being pivoted to a swiveled means carried on one of said control elements.

6. In a dual control, two control elements, pivoted for fore and aft, and lateral, movement, a single rigid connecting means to transmit fore and aft, and lateral move ment from one control element to the other, said rigid connecting means being pivoted to one of said control elements and being pivoted to a sleeve carried by and rotatable with respect to the other of said control elements.

7. In a dual control, two control elements, pivoted for fore and aft, and lateral movement, one of said elements being pivoted to trol elements, pivoted to each of said control elements at its opposite ends at a point spaced from the pivot of the respective control element, said rigid means functioning to transmit both fore and aft, and

lateral movement, from one of said control elements to the other, said rigid element being the sole connecting means between said control elements.

8. The combination as claimed in claim 7, in combination with a thrust bearing associated with said tube.

9. The combination as claimed in claim 3, said rigid connecting element being pivoted to a member swiveled on one of said control elements.

In testimony whereof we aflix our signatures.

ISAAC M. LADDON. DONALD H. REEVES. 

